I don't think the sword arts used by zenos are magic really but unique to the swords themselves... otherwise why use multiple swords? They made a huge deal about finding the one sword which was a power up of sorts for zenos and his abilities... the resonance let him overcome shinryu and merge with it (perhaps exhorting his will over the primal which in turn fused with zenos on command)... also why.didn't we take the damn sword with us after he killed himself? As a Sam main I was like... ma new sword, awwww...